The present invention relates to hoof protection and, in particular, to a shoe which allows the natural biomechanics of the hoof to operate while affording protection.
The present invention relates to hoof protection and, in particular, to a horseshoe fabricated from a non-metallic material and designed to protect a hoof by imparting conformance of hoof movement akin to that of healthy, active, unshod horses living in a natural environment. The invention relates to a horseshoe which has the ability to flex so as to assume a shape and width that aids in the natural splaying of the hoof. In addition, the invention relates to a horseshoe which includes a resilient material for attenuating shock and vibration associated with use and to provide maximum traction.
Horseshoes have been used for centuries in order to afford protection to the horse""s hoof and to enhance performance. Most horseshoes in use today are made of metal such as steel, aluminum alloys, and, rarely, stainless steel or titanium. Aluminum alloys are most commonly used today in racing and such are characterized by relatively low weight and expense. Alternatively, horseshoes are also made from various plastics, rubber, or composite materials. However, plastic, rubber. or composite horseshoes have not substantially replaced more conventional metal horseshoes in the marketplace. This is largely due to the existence of outstanding questions or problems regarding the durability, weight, expense, biomechanical functionality, or possible adverse health effects associated with such horseshoes. In particular, the use of some plastic materials and/or the adhesives used to bond the plastic horseshoe to a horse""s foot has sometimes led to illness, as these materials can release chemicals which are capable of migrating or diffusing through the horse""s hoof into the horse""s body.
The surfaces on which horses perform also vary widely. Horses frequently move about on natural ground of grass, sand, cinder, crushed stone, and sometimes on packed surfaces which nearly approach the hardness of asphalt or cement. The hardness and texture of surfaces can greatly increase the effective rate of loading, thus, the shock and vibration which may affect the hoof. Such will necessarily influence the nature of the impact on the hoof transmitted by use. The factors of use directly affect the horse""s efficiency, and the amount of trauma that will be experienced by the hoof. Accordingly, it can be understood that the potential for injury is large whenever horses navigate on surfaces that are detrimental to the hoof.
The teachings of the present invention can be better appreciated if the biomechanical events associated with the phenomena under discussion are understood. The method by which the hoof of a horse contacts the ground and propels a horse forward may contribute to an understanding of the present invention. What normally happens as a horse""s hoof impacts the ground is that the back of the hoof touches first, then the hoof flattens and slides forward skating across the surface. In particular, this is true of the horse""s rear hoof when the rear portion of the hoof is loaded and splaying takes place. This will generally cause the hoof to rotate backwards at the heel. The hoof will then rotate forward and recover to a relatively neutral position. Subsequently, the hoof rapidly rotates forward about a rocker point located between the geometric center of the hoof and a short distance behind the anterior-most area of the toe as the hoof breaks over and the toe-off takes place, thus, ending the ground support phase and beginning the flight phase.
It is known that the hoof of an active unshod horse living in a natural environment will wear such that the front and back of the hoof become gently rounded. In fact, horseshoes which were initially substantially rectangular in cross section wear in these areas and eventually enable a combination of a horse""s hoof and horseshoe to assume a somewhat similar shape. Unfortunately, many conventional horseshoes are so constructed as to require replacement by the time this more natural configuration is attained. The propulsive phase occurs when the hoof is used to propel the horse. The ability of a horse""s hoof to slide somewhat can also enhance the stability when a horse""s hoof will suddenly catch or grab the ground. Of course, the presence of extremely loose or slippery ground can neutralize the possible adverse affects of such traction devices and, in fact, such may provide better performance and safety in such circumstances.
It is also known that the hoof of an active unshod horse living in a natural environment will assume a slightly arcuate concave shape in the toe area between the medial line and lateral sides as when viewed from the front and also along sides of the hoof between the toe and the heel. This configuration permits the hoof to better slide or plane over the ground support surface during the impact phase as impact takes place, thereby reducing the effective rate of loading and the shock and vibration experienced.
Furthermore, it is known that in the unshod natural state a horse""s foot will flex and slightly widen when it is loaded. Discussion of this known phenomena is found in U.S. Pat. No. 4,513,824 granted to Donald F. Ford on Apr. 30, 1985. The use of a relatively rigid metal or aluminum horseshoe substantially prevents this natural movement and so tends to reduce both the effective size and the shock and vibration absorbing capability of a horse""s foot. A plastic horseshoe is known to be more flexible in this regard than an aluminum, steel, or titanium horseshoe. It is believed that the occurrence of hoof cracks is sometimes caused by the flexing and widening action of the foot and hoof working against the nails associated with a substantially inflexible horseshoe.
It is known that, when shod, the downward movement of the center of the horse""s foot can sometimes impact the inner upper edge of a conventional horseshoe, as such may not perfectly fit the shape of the horse""s foot or otherwise accommodate for this movement. Horses engaged in use by riding are commonly re-shod every four to six weeks. This is done in consideration for the wear incurred by the horseshoes, but also by the desire to maintain a healthy geometry with respect to the configuration of the hoof and to facilitate optimal biomechanics during use of the hoof.
One of the challenges encountered when attempting to reduce the rate of loading, and attenuate the shock and vibration experienced by a horse is posed by the fact that a horse is a rather large animal, commonly weighing between 800 and 1,400 pounds and, when running at speeds of 30 to 40 miles per hour, the load can exceed 15,000 pounds at each step. Accordingly, approximately 2,600 pounds per square inch can be placed upon a typical horseshoe having roughly 6.5 square inches of working surface. By way of comparison, humans commonly experience something in the range of approximately 18 pounds per square inch when running on asphalt in quality athletic footwear. The most distal bone proximate on the horse""s hoof corresponds to the most distal phalange in the tip of the finger or toe of the human hand or foot. All things considered, it is perhaps surprising that equine injuries are not more common.
The prior art confers some advantages over the unshod hoof in that the traditional metal horseshoe protects the hoof from injury due to sharp objects and uneven wear of the hoof and further provides means of traction greater than that afforded a naturally existing hoof. Disadvantages of the prior art include the fact that the frog portion of the hoof, when unprotected during use, has an increased likelihood of injury from the lack of frog protection. Further, the natural splaying of the hoof experienced by the horse during use is impeded to the rigid nature of the prior art. Still further, the recessed portion of the present invention allows maximum natural splay of the horse""s hoof while still protecting the hoof and the frog portion of the hoof from contact with sharp objects.
An object of the present invention is to provide a horseshoe that will facilitate the natural widening and flexing movement of the horse""s foot and hoof while still providing the protection and wear afforded by conventional horseshoes.
A further object of the present invention is to provide a horseshoe with space for flexation and expansion of the frog area of the horse""s hoof as the horse""s foot is loaded.
It is an object of the present invention to reduce the rate of loading and attenuate the shock and vibration which is experienced by a horse when walking or running.
It is an object of the present invention to provide a horseshoe that allows the frog portion of the hoof to naturally expand as weight is put upon the hoof.
It is an object of the present invention to provide a recessed frog protector such that even when undergoing splaying the frog is protected.
It is further an object of the present invention to allow the sole portion of the hoof to be sufficiently exposed to the ambient air so as to inhibit diseases commonly associated with the binding of the hoof.
It is an object of the present invention to provide a horseshoe which does not substantially elevate the horse""s hoof above the height of conventional metal horseshoes, thus, minimizing the possible introduction of instability.
A further object of the present invention to minimize the amount of plastic or rubber material which is placed in communication with the horse""s hoof.
Further, an object of the present invention is to use plastic or rubber materials which are known to be relatively harmless and not subject to such degradation.
An object of the present invention is to have the shoe directly in contact with the hoof thereby avoiding squirming of the horseshoe, damage to the nails, damage to the shoe itself, and perhaps catastrophic loss of a horseshoe during use.
A further object of the present invention is to provide a light weight shoe to avoid trauma to joints and connective tissue and alterations in a horse""s biomechanics, or a way of going which can be inefficient and result in interference.
It is further an object of the present invention to reduce the magnitude of the loads, shock, and vibration as may be experienced by the horse during walking or running.
A further object of the present invention is to provide superior traction to the horse so that locomotion is enhanced.
A further object of the present invention is to provide a rollover toe to avoid stubbing and aid in motion. The shape of the present invention allows fitting of both oval and round hoof shapes and uses a trim guide to aid in cutting away excess shoe.